The first space probe to take pictures of Mars’ surface was Mariner 4 in 1964.

Mars is the most studied planet of the solar system. There are three spacecraft down on the surface of Mars, NASA’s Spirit and Opportunity rovers, as well as the Phoenix Mars lander. And there are three orbiters watching from orbit: NASA’s Mars Reconnaissance Orbiter, Mars Odyssey and ESA’s Mars Express.

Rocks from Mars have landed on Earth, from meteorite impacts blasting debris through space. These also help scientists in studying Mars.

In the future, there could be airplanes and balloons, subsurface explorers, and maybe even sample return missions, to bring a little piece of Mars back to Earth. One day, humans will finally step foot on the Red Planet. Maybe even within our lifetime.

On September 28, 2015, NASA announced that they had found conclusive evidence of hydrated brine flows on recurring slope lineae, based on spectrometer readings of the darkened areas of slopes.